This bug was fixed in the package gnome-boxes - 3.22.1-0ubuntu1
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gnome-boxes (3.22.1-0ubuntu1) yakkety; urgency=medium
* New upstream bugfix release (LP: #1631585)
- Fix screen resolution change notification with GTK+ 3.22
-- Jeremy Bicha Sat, 08 Oct 2016 06:22:42 -0400
** Description changed:
Impact
==
- Only two commits this time.
+ Only two commits this time. One commit fixes an issue triggered by vala 0.34
(although yakkety only has vala 0.32).
+
+ The other fixes a runtime console warning and missing screen resolution
+ notification with GTK 3.22.
